diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/nilfs2/recovery.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/nilfs2/recovery.c | 963 |
1 files changed, 0 insertions, 963 deletions
diff --git a/ANDROID_3.4.5/fs/nilfs2/recovery.c b/ANDROID_3.4.5/fs/nilfs2/recovery.c deleted file mode 100644 index f1626f50..00000000 --- a/ANDROID_3.4.5/fs/nilfs2/recovery.c +++ /dev/null @@ -1,963 +0,0 @@ -/* - * recovery.c - NILFS recovery logic - * - * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - * - * Written by Ryusuke Konishi <ryusuke@osrg.net> - */ - -#include <linux/buffer_head.h> -#include <linux/blkdev.h> -#include <linux/swap.h> -#include <linux/slab.h> -#include <linux/crc32.h> -#include "nilfs.h" -#include "segment.h" -#include "sufile.h" -#include "page.h" -#include "segbuf.h" - -/* - * Segment check result - */ -enum { - NILFS_SEG_VALID, - NILFS_SEG_NO_SUPER_ROOT, - NILFS_SEG_FAIL_IO, - NILFS_SEG_FAIL_MAGIC, - NILFS_SEG_FAIL_SEQ, - NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT, - NILFS_SEG_FAIL_CHECKSUM_FULL, - NILFS_SEG_FAIL_CONSISTENCY, -}; - -/* work structure for recovery */ -struct nilfs_recovery_block { - ino_t ino; /* Inode number of the file that this block - belongs to */ - sector_t blocknr; /* block number */ - __u64 vblocknr; /* virtual block number */ - unsigned long blkoff; /* File offset of the data block (per block) */ - struct list_head list; -}; - - -static int nilfs_warn_segment_error(int err) -{ - switch (err) { - case NILFS_SEG_FAIL_IO: - printk(KERN_WARNING - "NILFS warning: I/O error on loading last segment\n"); - return -EIO; - case NILFS_SEG_FAIL_MAGIC: - printk(KERN_WARNING - "NILFS warning: Segment magic number invalid\n"); - break; - case NILFS_SEG_FAIL_SEQ: - printk(KERN_WARNING - "NILFS warning: Sequence number mismatch\n"); - break; - case NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT: - printk(KERN_WARNING - "NILFS warning: Checksum error in super root\n"); - break; - case NILFS_SEG_FAIL_CHECKSUM_FULL: - printk(KERN_WARNING - "NILFS warning: Checksum error in segment payload\n"); - break; - case NILFS_SEG_FAIL_CONSISTENCY: - printk(KERN_WARNING - "NILFS warning: Inconsistent segment\n"); - break; - case NILFS_SEG_NO_SUPER_ROOT: - printk(KERN_WARNING - "NILFS warning: No super root in the last segment\n"); - break; - } - return -EINVAL; -} - -/** - * nilfs_compute_checksum - compute checksum of blocks continuously - * @nilfs: nilfs object - * @bhs: buffer head of start block - * @sum: place to store result - * @offset: offset bytes in the first block - * @check_bytes: number of bytes to be checked - * @start: DBN of start block - * @nblock: number of blocks to be checked - */ -static int nilfs_compute_checksum(struct the_nilfs *nilfs, - struct buffer_head *bhs, u32 *sum, - unsigned long offset, u64 check_bytes, - sector_t start, unsigned long nblock) -{ - unsigned int blocksize = nilfs->ns_blocksize; - unsigned long size; - u32 crc; - - BUG_ON(offset >= blocksize); - check_bytes -= offset; - size = min_t(u64, check_bytes, blocksize - offset); - crc = crc32_le(nilfs->ns_crc_seed, - (unsigned char *)bhs->b_data + offset, size); - if (--nblock > 0) { - do { - struct buffer_head *bh; - - bh = __bread(nilfs->ns_bdev, ++start, blocksize); - if (!bh) - return -EIO; - check_bytes -= size; - size = min_t(u64, check_bytes, blocksize); - crc = crc32_le(crc, bh->b_data, size); - brelse(bh); - } while (--nblock > 0); - } - *sum = crc; - return 0; -} - -/** - * nilfs_read_super_root_block - read super root block - * @nilfs: nilfs object - * @sr_block: disk block number of the super root block - * @pbh: address of a buffer_head pointer to return super root buffer - * @check: CRC check flag - */ -int nilfs_read_super_root_block(struct the_nilfs *nilfs, sector_t sr_block, - struct buffer_head **pbh, int check) -{ - struct buffer_head *bh_sr; - struct nilfs_super_root *sr; - u32 crc; - int ret; - - *pbh = NULL; - bh_sr = __bread(nilfs->ns_bdev, sr_block, nilfs->ns_blocksize); - if (unlikely(!bh_sr)) { - ret = NILFS_SEG_FAIL_IO; - goto failed; - } - - sr = (struct nilfs_super_root *)bh_sr->b_data; - if (check) { - unsigned bytes = le16_to_cpu(sr->sr_bytes); - - if (bytes == 0 || bytes > nilfs->ns_blocksize) { - ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; - goto failed_bh; - } - if (nilfs_compute_checksum( - nilfs, bh_sr, &crc, sizeof(sr->sr_sum), bytes, - sr_block, 1)) { - ret = NILFS_SEG_FAIL_IO; - goto failed_bh; - } - if (crc != le32_to_cpu(sr->sr_sum)) { - ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT; - goto failed_bh; - } - } - *pbh = bh_sr; - return 0; - - failed_bh: - brelse(bh_sr); - - failed: - return nilfs_warn_segment_error(ret); -} - -/** - * nilfs_read_log_header - read summary header of the specified log - * @nilfs: nilfs object - * @start_blocknr: start block number of the log - * @sum: pointer to return segment summary structure - */ -static struct buffer_head * -nilfs_read_log_header(struct the_nilfs *nilfs, sector_t start_blocknr, - struct nilfs_segment_summary **sum) -{ - struct buffer_head *bh_sum; - - bh_sum = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize); - if (bh_sum) - *sum = (struct nilfs_segment_summary *)bh_sum->b_data; - return bh_sum; -} - -/** - * nilfs_validate_log - verify consistency of log - * @nilfs: nilfs object - * @seg_seq: sequence number of segment - * @bh_sum: buffer head of summary block - * @sum: segment summary struct - */ -static int nilfs_validate_log(struct the_nilfs *nilfs, u64 seg_seq, - struct buffer_head *bh_sum, - struct nilfs_segment_summary *sum) -{ - unsigned long nblock; - u32 crc; - int ret; - - ret = NILFS_SEG_FAIL_MAGIC; - if (le32_to_cpu(sum->ss_magic) != NILFS_SEGSUM_MAGIC) - goto out; - - ret = NILFS_SEG_FAIL_SEQ; - if (le64_to_cpu(sum->ss_seq) != seg_seq) - goto out; - - nblock = le32_to_cpu(sum->ss_nblocks); - ret = NILFS_SEG_FAIL_CONSISTENCY; - if (unlikely(nblock == 0 || nblock > nilfs->ns_blocks_per_segment)) - /* This limits the number of blocks read in the CRC check */ - goto out; - - ret = NILFS_SEG_FAIL_IO; - if (nilfs_compute_checksum(nilfs, bh_sum, &crc, sizeof(sum->ss_datasum), - ((u64)nblock << nilfs->ns_blocksize_bits), - bh_sum->b_blocknr, nblock)) - goto out; - - ret = NILFS_SEG_FAIL_CHECKSUM_FULL; - if (crc != le32_to_cpu(sum->ss_datasum)) - goto out; - ret = 0; -out: - return ret; -} - -/** - * nilfs_read_summary_info - read an item on summary blocks of a log - * @nilfs: nilfs object - * @pbh: the current buffer head on summary blocks [in, out] - * @offset: the current byte offset on summary blocks [in, out] - * @bytes: byte size of the item to be read - */ -static void *nilfs_read_summary_info(struct the_nilfs *nilfs, - struct buffer_head **pbh, - unsigned int *offset, unsigned int bytes) -{ - void *ptr; - sector_t blocknr; - - BUG_ON((*pbh)->b_size < *offset); - if (bytes > (*pbh)->b_size - *offset) { - blocknr = (*pbh)->b_blocknr; - brelse(*pbh); - *pbh = __bread(nilfs->ns_bdev, blocknr + 1, - nilfs->ns_blocksize); - if (unlikely(!*pbh)) - return NULL; - *offset = 0; - } - ptr = (*pbh)->b_data + *offset; - *offset += bytes; - return ptr; -} - -/** - * nilfs_skip_summary_info - skip items on summary blocks of a log - * @nilfs: nilfs object - * @pbh: the current buffer head on summary blocks [in, out] - * @offset: the current byte offset on summary blocks [in, out] - * @bytes: byte size of the item to be skipped - * @count: number of items to be skipped - */ -static void nilfs_skip_summary_info(struct the_nilfs *nilfs, - struct buffer_head **pbh, - unsigned int *offset, unsigned int bytes, - unsigned long count) -{ - unsigned int rest_item_in_current_block - = ((*pbh)->b_size - *offset) / bytes; - - if (count <= rest_item_in_current_block) { - *offset += bytes * count; - } else { - sector_t blocknr = (*pbh)->b_blocknr; - unsigned int nitem_per_block = (*pbh)->b_size / bytes; - unsigned int bcnt; - - count -= rest_item_in_current_block; - bcnt = DIV_ROUND_UP(count, nitem_per_block); - *offset = bytes * (count - (bcnt - 1) * nitem_per_block); - - brelse(*pbh); - *pbh = __bread(nilfs->ns_bdev, blocknr + bcnt, - nilfs->ns_blocksize); - } -} - -/** - * nilfs_scan_dsync_log - get block information of a log written for data sync - * @nilfs: nilfs object - * @start_blocknr: start block number of the log - * @sum: log summary information - * @head: list head to add nilfs_recovery_block struct - */ -static int nilfs_scan_dsync_log(struct the_nilfs *nilfs, sector_t start_blocknr, - struct nilfs_segment_summary *sum, - struct list_head *head) -{ - struct buffer_head *bh; - unsigned int offset; - u32 nfinfo, sumbytes; - sector_t blocknr; - ino_t ino; - int err = -EIO; - - nfinfo = le32_to_cpu(sum->ss_nfinfo); - if (!nfinfo) - return 0; - - sumbytes = le32_to_cpu(sum->ss_sumbytes); - blocknr = start_blocknr + DIV_ROUND_UP(sumbytes, nilfs->ns_blocksize); - bh = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize); - if (unlikely(!bh)) - goto out; - - offset = le16_to_cpu(sum->ss_bytes); - for (;;) { - unsigned long nblocks, ndatablk, nnodeblk; - struct nilfs_finfo *finfo; - - finfo = nilfs_read_summary_info(nilfs, &bh, &offset, - sizeof(*finfo)); - if (unlikely(!finfo)) - goto out; - - ino = le64_to_cpu(finfo->fi_ino); - nblocks = le32_to_cpu(finfo->fi_nblocks); - ndatablk = le32_to_cpu(finfo->fi_ndatablk); - nnodeblk = nblocks - ndatablk; - - while (ndatablk-- > 0) { - struct nilfs_recovery_block *rb; - struct nilfs_binfo_v *binfo; - - binfo = nilfs_read_summary_info(nilfs, &bh, &offset, - sizeof(*binfo)); - if (unlikely(!binfo)) - goto out; - - rb = kmalloc(sizeof(*rb), GFP_NOFS); - if (unlikely(!rb)) { - err = -ENOMEM; - goto out; - } - rb->ino = ino; - rb->blocknr = blocknr++; - rb->vblocknr = le64_to_cpu(binfo->bi_vblocknr); - rb->blkoff = le64_to_cpu(binfo->bi_blkoff); - /* INIT_LIST_HEAD(&rb->list); */ - list_add_tail(&rb->list, head); - } - if (--nfinfo == 0) - break; - blocknr += nnodeblk; /* always 0 for data sync logs */ - nilfs_skip_summary_info(nilfs, &bh, &offset, sizeof(__le64), - nnodeblk); - if (unlikely(!bh)) - goto out; - } - err = 0; - out: - brelse(bh); /* brelse(NULL) is just ignored */ - return err; -} - -static void dispose_recovery_list(struct list_head *head) -{ - while (!list_empty(head)) { - struct nilfs_recovery_block *rb; - - rb = list_first_entry(head, struct nilfs_recovery_block, list); - list_del(&rb->list); - kfree(rb); - } -} - -struct nilfs_segment_entry { - struct list_head list; - __u64 segnum; -}; - -static int nilfs_segment_list_add(struct list_head *head, __u64 segnum) -{ - struct nilfs_segment_entry *ent = kmalloc(sizeof(*ent), GFP_NOFS); - - if (unlikely(!ent)) - return -ENOMEM; - - ent->segnum = segnum; - INIT_LIST_HEAD(&ent->list); - list_add_tail(&ent->list, head); - return 0; -} - -void nilfs_dispose_segment_list(struct list_head *head) -{ - while (!list_empty(head)) { - struct nilfs_segment_entry *ent; - - ent = list_first_entry(head, struct nilfs_segment_entry, list); - list_del(&ent->list); - kfree(ent); - } -} - -static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs, - struct super_block *sb, - struct nilfs_recovery_info *ri) -{ - struct list_head *head = &ri->ri_used_segments; - struct nilfs_segment_entry *ent, *n; - struct inode *sufile = nilfs->ns_sufile; - __u64 segnum[4]; - int err; - int i; - - segnum[0] = nilfs->ns_segnum; - segnum[1] = nilfs->ns_nextnum; - segnum[2] = ri->ri_segnum; - segnum[3] = ri->ri_nextnum; - - /* - * Releasing the next segment of the latest super root. - * The next segment is invalidated by this recovery. - */ - err = nilfs_sufile_free(sufile, segnum[1]); - if (unlikely(err)) - goto failed; - - for (i = 1; i < 4; i++) { - err = nilfs_segment_list_add(head, segnum[i]); - if (unlikely(err)) - goto failed; - } - - /* - * Collecting segments written after the latest super root. - * These are marked dirty to avoid being reallocated in the next write. - */ - list_for_each_entry_safe(ent, n, head, list) { - if (ent->segnum != segnum[0]) { - err = nilfs_sufile_scrap(sufile, ent->segnum); - if (unlikely(err)) - goto failed; - } - list_del(&ent->list); - kfree(ent); - } - - /* Allocate new segments for recovery */ - err = nilfs_sufile_alloc(sufile, &segnum[0]); - if (unlikely(err)) - goto failed; - - nilfs->ns_pseg_offset = 0; - nilfs->ns_seg_seq = ri->ri_seq + 2; - nilfs->ns_nextnum = nilfs->ns_segnum = segnum[0]; - - failed: - /* No need to recover sufile because it will be destroyed on error */ - return err; -} - -static int nilfs_recovery_copy_block(struct the_nilfs *nilfs, - struct nilfs_recovery_block *rb, - struct page *page) -{ - struct buffer_head *bh_org; - void *kaddr; - - bh_org = __bread(nilfs->ns_bdev, rb->blocknr, nilfs->ns_blocksize); - if (unlikely(!bh_org)) - return -EIO; - - kaddr = kmap_atomic(page); - memcpy(kaddr + bh_offset(bh_org), bh_org->b_data, bh_org->b_size); - kunmap_atomic(kaddr); - brelse(bh_org); - return 0; -} - -static int nilfs_recover_dsync_blocks(struct the_nilfs *nilfs, - struct super_block *sb, - struct nilfs_root *root, - struct list_head *head, - unsigned long *nr_salvaged_blocks) -{ - struct inode *inode; - struct nilfs_recovery_block *rb, *n; - unsigned blocksize = nilfs->ns_blocksize; - struct page *page; - loff_t pos; - int err = 0, err2 = 0; - - list_for_each_entry_safe(rb, n, head, list) { - inode = nilfs_iget(sb, root, rb->ino); - if (IS_ERR(inode)) { - err = PTR_ERR(inode); - inode = NULL; - goto failed_inode; - } - - pos = rb->blkoff << inode->i_blkbits; - err = block_write_begin(inode->i_mapping, pos, blocksize, - 0, &page, nilfs_get_block); - if (unlikely(err)) { - loff_t isize = inode->i_size; - if (pos + blocksize > isize) - vmtruncate(inode, isize); - goto failed_inode; - } - - err = nilfs_recovery_copy_block(nilfs, rb, page); - if (unlikely(err)) - goto failed_page; - - err = nilfs_set_file_dirty(inode, 1); - if (unlikely(err)) - goto failed_page; - - block_write_end(NULL, inode->i_mapping, pos, blocksize, - blocksize, page, NULL); - - unlock_page(page); - page_cache_release(page); - - (*nr_salvaged_blocks)++; - goto next; - - failed_page: - unlock_page(page); - page_cache_release(page); - - failed_inode: - printk(KERN_WARNING - "NILFS warning: error recovering data block " - "(err=%d, ino=%lu, block-offset=%llu)\n", - err, (unsigned long)rb->ino, - (unsigned long long)rb->blkoff); - if (!err2) - err2 = err; - next: - iput(inode); /* iput(NULL) is just ignored */ - list_del_init(&rb->list); - kfree(rb); - } - return err2; -} - -/** - * nilfs_do_roll_forward - salvage logical segments newer than the latest - * checkpoint - * @nilfs: nilfs object - * @sb: super block instance - * @ri: pointer to a nilfs_recovery_info - */ -static int nilfs_do_roll_forward(struct the_nilfs *nilfs, - struct super_block *sb, - struct nilfs_root *root, - struct nilfs_recovery_info *ri) -{ - struct buffer_head *bh_sum = NULL; - struct nilfs_segment_summary *sum; - sector_t pseg_start; - sector_t seg_start, seg_end; /* Starting/ending DBN of full segment */ - unsigned long nsalvaged_blocks = 0; - unsigned int flags; - u64 seg_seq; - __u64 segnum, nextnum = 0; - int empty_seg = 0; - int err = 0, ret; - LIST_HEAD(dsync_blocks); /* list of data blocks to be recovered */ - enum { - RF_INIT_ST, - RF_DSYNC_ST, /* scanning data-sync segments */ - }; - int state = RF_INIT_ST; - - pseg_start = ri->ri_lsegs_start; - seg_seq = ri->ri_lsegs_start_seq; - segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); - nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); - - while (segnum != ri->ri_segnum || pseg_start <= ri->ri_pseg_start) { - brelse(bh_sum); - bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum); - if (!bh_sum) { - err = -EIO; - goto failed; - } - - ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum); - if (ret) { - if (ret == NILFS_SEG_FAIL_IO) { - err = -EIO; - goto failed; - } - goto strayed; - } - - flags = le16_to_cpu(sum->ss_flags); - if (flags & NILFS_SS_SR) - goto confused; - - /* Found a valid partial segment; do recovery actions */ - nextnum = nilfs_get_segnum_of_block(nilfs, - le64_to_cpu(sum->ss_next)); - empty_seg = 0; - nilfs->ns_ctime = le64_to_cpu(sum->ss_create); - if (!(flags & NILFS_SS_GC)) - nilfs->ns_nongc_ctime = nilfs->ns_ctime; - - switch (state) { - case RF_INIT_ST: - if (!(flags & NILFS_SS_LOGBGN) || - !(flags & NILFS_SS_SYNDT)) - goto try_next_pseg; - state = RF_DSYNC_ST; - /* Fall through */ - case RF_DSYNC_ST: - if (!(flags & NILFS_SS_SYNDT)) - goto confused; - - err = nilfs_scan_dsync_log(nilfs, pseg_start, sum, - &dsync_blocks); - if (unlikely(err)) - goto failed; - if (flags & NILFS_SS_LOGEND) { - err = nilfs_recover_dsync_blocks( - nilfs, sb, root, &dsync_blocks, - &nsalvaged_blocks); - if (unlikely(err)) - goto failed; - state = RF_INIT_ST; - } - break; /* Fall through to try_next_pseg */ - } - - try_next_pseg: - if (pseg_start == ri->ri_lsegs_end) - break; - pseg_start += le32_to_cpu(sum->ss_nblocks); - if (pseg_start < seg_end) - continue; - goto feed_segment; - - strayed: - if (pseg_start == ri->ri_lsegs_end) - break; - - feed_segment: - /* Looking to the next full segment */ - if (empty_seg++) - break; - seg_seq++; - segnum = nextnum; - nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); - pseg_start = seg_start; - } - - if (nsalvaged_blocks) { - printk(KERN_INFO "NILFS (device %s): salvaged %lu blocks\n", - sb->s_id, nsalvaged_blocks); - ri->ri_need_recovery = NILFS_RECOVERY_ROLLFORWARD_DONE; - } - out: - brelse(bh_sum); - dispose_recovery_list(&dsync_blocks); - return err; - - confused: - err = -EINVAL; - failed: - printk(KERN_ERR - "NILFS (device %s): Error roll-forwarding " - "(err=%d, pseg block=%llu). ", - sb->s_id, err, (unsigned long long)pseg_start); - goto out; -} - -static void nilfs_finish_roll_forward(struct the_nilfs *nilfs, - struct nilfs_recovery_info *ri) -{ - struct buffer_head *bh; - int err; - - if (nilfs_get_segnum_of_block(nilfs, ri->ri_lsegs_start) != - nilfs_get_segnum_of_block(nilfs, ri->ri_super_root)) - return; - - bh = __getblk(nilfs->ns_bdev, ri->ri_lsegs_start, nilfs->ns_blocksize); - BUG_ON(!bh); - memset(bh->b_data, 0, bh->b_size); - set_buffer_dirty(bh); - err = sync_dirty_buffer(bh); - if (unlikely(err)) - printk(KERN_WARNING - "NILFS warning: buffer sync write failed during " - "post-cleaning of recovery.\n"); - brelse(bh); -} - -/** - * nilfs_salvage_orphan_logs - salvage logs written after the latest checkpoint - * @nilfs: nilfs object - * @sb: super block instance - * @ri: pointer to a nilfs_recovery_info struct to store search results. - * - * Return Value: On success, 0 is returned. On error, one of the following - * negative error code is returned. - * - * %-EINVAL - Inconsistent filesystem state. - * - * %-EIO - I/O error - * - * %-ENOSPC - No space left on device (only in a panic state). - * - * %-ERESTARTSYS - Interrupted. - * - * %-ENOMEM - Insufficient memory available. - */ -int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs, - struct super_block *sb, - struct nilfs_recovery_info *ri) -{ - struct nilfs_root *root; - int err; - - if (ri->ri_lsegs_start == 0 || ri->ri_lsegs_end == 0) - return 0; - - err = nilfs_attach_checkpoint(sb, ri->ri_cno, true, &root); - if (unlikely(err)) { - printk(KERN_ERR - "NILFS: error loading the latest checkpoint.\n"); - return err; - } - - err = nilfs_do_roll_forward(nilfs, sb, root, ri); - if (unlikely(err)) - goto failed; - - if (ri->ri_need_recovery == NILFS_RECOVERY_ROLLFORWARD_DONE) { - err = nilfs_prepare_segment_for_recovery(nilfs, sb, ri); - if (unlikely(err)) { - printk(KERN_ERR "NILFS: Error preparing segments for " - "recovery.\n"); - goto failed; - } - - err = nilfs_attach_log_writer(sb, root); - if (unlikely(err)) - goto failed; - - set_nilfs_discontinued(nilfs); - err = nilfs_construct_segment(sb); - nilfs_detach_log_writer(sb); - - if (unlikely(err)) { - printk(KERN_ERR "NILFS: Oops! recovery failed. " - "(err=%d)\n", err); - goto failed; - } - - nilfs_finish_roll_forward(nilfs, ri); - } - - failed: - nilfs_put_root(root); - return err; -} - -/** - * nilfs_search_super_root - search the latest valid super root - * @nilfs: the_nilfs - * @ri: pointer to a nilfs_recovery_info struct to store search results. - * - * nilfs_search_super_root() looks for the latest super-root from a partial - * segment pointed by the superblock. It sets up struct the_nilfs through - * this search. It fills nilfs_recovery_info (ri) required for recovery. - * - * Return Value: On success, 0 is returned. On error, one of the following - * negative error code is returned. - * - * %-EINVAL - No valid segment found - * - * %-EIO - I/O error - * - * %-ENOMEM - Insufficient memory available. - */ -int nilfs_search_super_root(struct the_nilfs *nilfs, - struct nilfs_recovery_info *ri) -{ - struct buffer_head *bh_sum = NULL; - struct nilfs_segment_summary *sum; - sector_t pseg_start, pseg_end, sr_pseg_start = 0; - sector_t seg_start, seg_end; /* range of full segment (block number) */ - sector_t b, end; - unsigned long nblocks; - unsigned int flags; - u64 seg_seq; - __u64 segnum, nextnum = 0; - __u64 cno; - LIST_HEAD(segments); - int empty_seg = 0, scan_newer = 0; - int ret; - - pseg_start = nilfs->ns_last_pseg; - seg_seq = nilfs->ns_last_seq; - cno = nilfs->ns_last_cno; - segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); - - /* Calculate range of segment */ - nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); - - /* Read ahead segment */ - b = seg_start; - while (b <= seg_end) - __breadahead(nilfs->ns_bdev, b++, nilfs->ns_blocksize); - - for (;;) { - brelse(bh_sum); - ret = NILFS_SEG_FAIL_IO; - bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum); - if (!bh_sum) - goto failed; - - ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum); - if (ret) { - if (ret == NILFS_SEG_FAIL_IO) - goto failed; - goto strayed; - } - - nblocks = le32_to_cpu(sum->ss_nblocks); - pseg_end = pseg_start + nblocks - 1; - if (unlikely(pseg_end > seg_end)) { - ret = NILFS_SEG_FAIL_CONSISTENCY; - goto strayed; - } - - /* A valid partial segment */ - ri->ri_pseg_start = pseg_start; - ri->ri_seq = seg_seq; - ri->ri_segnum = segnum; - nextnum = nilfs_get_segnum_of_block(nilfs, - le64_to_cpu(sum->ss_next)); - ri->ri_nextnum = nextnum; - empty_seg = 0; - - flags = le16_to_cpu(sum->ss_flags); - if (!(flags & NILFS_SS_SR) && !scan_newer) { - /* This will never happen because a superblock - (last_segment) always points to a pseg - having a super root. */ - ret = NILFS_SEG_FAIL_CONSISTENCY; - goto failed; - } - - if (pseg_start == seg_start) { - nilfs_get_segment_range(nilfs, nextnum, &b, &end); - while (b <= end) - __breadahead(nilfs->ns_bdev, b++, - nilfs->ns_blocksize); - } - if (!(flags & NILFS_SS_SR)) { - if (!ri->ri_lsegs_start && (flags & NILFS_SS_LOGBGN)) { - ri->ri_lsegs_start = pseg_start; - ri->ri_lsegs_start_seq = seg_seq; - } - if (flags & NILFS_SS_LOGEND) - ri->ri_lsegs_end = pseg_start; - goto try_next_pseg; - } - - /* A valid super root was found. */ - ri->ri_cno = cno++; - ri->ri_super_root = pseg_end; - ri->ri_lsegs_start = ri->ri_lsegs_end = 0; - - nilfs_dispose_segment_list(&segments); - sr_pseg_start = pseg_start; - nilfs->ns_pseg_offset = pseg_start + nblocks - seg_start; - nilfs->ns_seg_seq = seg_seq; - nilfs->ns_segnum = segnum; - nilfs->ns_cno = cno; /* nilfs->ns_cno = ri->ri_cno + 1 */ - nilfs->ns_ctime = le64_to_cpu(sum->ss_create); - nilfs->ns_nextnum = nextnum; - - if (scan_newer) - ri->ri_need_recovery = NILFS_RECOVERY_SR_UPDATED; - else { - if (nilfs->ns_mount_state & NILFS_VALID_FS) - goto super_root_found; - scan_newer = 1; - } - - try_next_pseg: - /* Standing on a course, or met an inconsistent state */ - pseg_start += nblocks; - if (pseg_start < seg_end) - continue; - goto feed_segment; - - strayed: - /* Off the trail */ - if (!scan_newer) - /* - * This can happen if a checkpoint was written without - * barriers, or as a result of an I/O failure. - */ - goto failed; - - feed_segment: - /* Looking to the next full segment */ - if (empty_seg++) - goto super_root_found; /* found a valid super root */ - - ret = nilfs_segment_list_add(&segments, segnum); - if (unlikely(ret)) - goto failed; - - seg_seq++; - segnum = nextnum; - nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end); - pseg_start = seg_start; - } - - super_root_found: - /* Updating pointers relating to the latest checkpoint */ - brelse(bh_sum); - list_splice_tail(&segments, &ri->ri_used_segments); - nilfs->ns_last_pseg = sr_pseg_start; - nilfs->ns_last_seq = nilfs->ns_seg_seq; - nilfs->ns_last_cno = ri->ri_cno; - return 0; - - failed: - brelse(bh_sum); - nilfs_dispose_segment_list(&segments); - return (ret < 0) ? ret : nilfs_warn_segment_error(ret); -} |